This invention generally relates to printing or duplicating machines and, more particularly, to a system or mechanism for adjustably mounting distribution rollers for distributing moisture or ink to the printing couple of the machine.
Printing machines normally include a printing couple which comprises a number of cylinders and/or rollers such as impression cylinders, master cylinders, blanket cylinders, ductor rollers, transfer rollers, regulator rollers, and the like. For instance, an ink fountain is disposed generally at the rear of the machine for feeding ink to the various rollers of the printing couple which transfers images to copy sheets. In such printing machines as rotary offset lithographic duplicating machines, a moisture fountain also is disposed adjacent the printing couple for feeding moisture to the printing couple. A number of rollers which can be generally termed "distribution" rollers are provided between the moisture fountain and/or ink fountain for distributing moisture and/or ink to the printing couple of the machine.
The distribution rollers often are mounted in triangulated arrays, i.e. groups of three, whereby one roller defines distribution gaps with two other adjacent rollers. Throughout the complex system of rollers, the "gaps" or pressure between adjacent rollers must be capable of regulation or adjustment in order to regulate the flow of moisture or ink through the roller system to the printing couple. When a given roller is disposed for conjoint rotation with a pair of adjacent rollers to distribute moisture or ink in a path therebetween, it is most desirable to provide for adjustment of the single roller in at least two directions so that pressure between that roller and its adjacent rollers can be adjusted by regulating the single roller.
Heretofore, roller adjustment mechanisms have been extremely complicated. Often, the machine must be shut down in order to perform any adjustments. In some instances, one or more of the rollers may have to be removed, particularly the adjustable roller, in order to accomplish any adjustments.
It would be desirable to provide a pressure adjustment mechanism which is simple, effective and which can be adjusted to vary the pressure or "gap" between adjacent rollers without removing any single roller. This invention is directed to solving the above problems and satisfying such a need for a simple adjustment mechanism for the distribution rollers, which can be performed while the rollers are in position and still allowing removal of the adjustable roller.